Share Email Print
cover

Proceedings Paper

Novel scanning technique for ultraprecise measurement of slope and topography of flats, aspheres, and complex surfaces
Author(s): Ingolf Weingaertner; Michael Schulz
Format Member Price Non-Member Price
PDF $14.40 $18.00

Paper Abstract

A novel optical scanning technique for testing flats, aspheres and complex surfaces is presented, which offers ultra-precision for the measurement of slope and topography. The scanning technique is based on a combination of two principles, namely to perform difference measurements for slopes with large shears and to use only a single pentagon prism for the difference measurements, keeping the angular position of the pentagon prism constant in space. The combination of these two principles eliminates the influences of all first and second-order errors of the scanning facility, as this scanning technique is traced back exclusively to the units of angle and length. Especially whole-body movement of the artifact under test and distortion of the facility itself do not result in errors. The evaluation of difference measurements with large shears has become possible very recently with high accuracy and high lateral resolution because an error-free algorithm was developed. It is further a special feature of this technique that it measures differences of slopes and, consequently, allows the measurement of aspheres and complex surfaces with large asphericities.

Paper Details

Date Published: 6 September 1999
PDF: 9 pages
Proc. SPIE 3739, Optical Fabrication and Testing, (6 September 1999); doi: 10.1117/12.360154
Show Author Affiliations
Ingolf Weingaertner, Physikalisch-Technische Bundesanstalt (Germany)
Michael Schulz, Physikalisch-Technische Bundesanstalt (Germany)


Published in SPIE Proceedings Vol. 3739:
Optical Fabrication and Testing
Roland Geyl; Jonathan Maxwell, Editor(s)

© SPIE. Terms of Use
Back to Top